AMD has been talking about Fusion for years now. Over time, the term has sort of morphed from referring to specific future products to a general marketing catch-all designed to help people think of the CPU and GPU (graphics processing unit) as the same thing. Somewhere along the way the term effectively lost all real meaning, as delays in AMD's "combination CPU and GPU chip" allowed Intel to catch up to the idea. Today, later than planned and not ahead of rival Intel, AMD is finally shipping a single piece of silicon that combines a CPU and GPU.

Ready for a slew of code-names and alphabet soup? Let me break it down for you. AMD calls these new chips the first in the "Fusion family of APUs". That's right, Fusion now refers to not a specific product or general concept, but a family of products that will span multiple CPUs and platforms, all of them combining the CPU and GPU. AMD has decided to stop calling these chips "CPUs" at all, instead coining the new term APU, or "Accelerated Processing Units." This is really just marketing speak - Intel's new 2nd Generation Core processors are APUs as well by AMD's definition, as they combine the CPU and GPU into a single piece of silicon.

The specific chips launching today are part of the platform code-named Brazos. Really, it's one chip in a few different configurations. The lowest-power configuration was code-named Ontario, and will carry a "C" model number. The higher-power configuration was code-named Zacate, and will carry an "E" model number. You'll see what is referred to as the "AMD C-Series APU" or "AMD E-Series APU" on spec sheets. Here's how the speeds and feeds break down:

Believe it or not, all these parts are actually the exact same piece of silicon. E-series (Zacate) or C-series (Ontario), all these "Brazos platform" CPUs are actually the same tiny die - it's only 75 square millimeters, manufactured at TSMC on a 40nm process. The maximum TDP (thermal design power) is determined by how fast the chip runs, how many cores are active, and how the chip performs as it comes off the production line. For reference, Intel's highest-performing dual-core Atom CPU, the Atom N550, runs at 1.5 GHz and consumes a maximum of 8.5 watts.

While these new E and C-seires CPUs will compete with Atom processors in many ways, they are in many ways not directly comparable. The graphics processor built in to these CPUs is based on AMD's Radeon 6000 series architecture, with full DirectX 11 support and support for DirectCompute and OpenCL - features Intel can't match even in its new 2nd Generation Core processors' graphics. It also features AMD's UVD3 video decoder, essentially the same as you'll find in their latest Radeon desktop graphics cards. Performance should be quite high, too. The CPU cores in these Brazos chips (code-named "Bobcat"...I told you there were a lot of code names!) are entirely new. Despite being quite tiny, AMD promises about 90% the performance of a typical Athlon or Sempron processor core. While Intel's Atom CPUs are "in-order" processors, the Bobcat core is an "out-of-order" processor core, as is the case with nearly all other modern laptop and desktop CPUs. Out-of-order processors tend to be more complex, but also much faster and more responsive in an modern multitasking operating system environment.

Early benchmarks from test systems seem positive, showing that at least the E-350 model handily beats the Intel's Atom CPUs at most processor intensive tasks, while the integrated graphics core is leaps and bounds ahead of anything else. We'll have to reserve judgement for when we get hands-on with actual shipping notebooks using the processors, but they seem to be a very promising development for AMD. Battery life has long been a sore spot for AMD, as has its inability to compete in the sizeable netbook and ultra thin and light laptop segments. These new E-series and C-series CPUs (we'll avoid AMD's marketing trick of re-branding them APUs) are laser-targeted at these segments and should finally give the company the performance and battery life needed to go head-to-head with Intel in these markets. Expect to see a number of laptops announced at CES using these processors, and full lab-tested reviews of the first models here on PCWorld later this month.

Be sure to check out or CES 2011 page for more news and video from the show.

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